Pump-rod suspension device



Feb. 26, 1929.

E. E. STEVENSON "PUMP ROD SUSPENSION DEVICE 3 Shays-Sheet l FiledOct. 5, 1926 ffforf? Feb. 26, 1929. 1,703,214

- E. E. STEVENSON PUMP ROD SUSPENSION DEVICE Filed Oct. 5, 1926 Sheets-Sheet 2 Z/ 3/ r4 Fa flue/Y/vr. 541mm: Slew/26a Feb. 26, 1929.

E. E. STEVENSON PUMP ROD SUSPENSION DEVICE Filed Oct. 5, 1926 3 Sheets-Sheet 5 1306/2/01". Mum/21551900125021 Patented Feb. 26,1929.

UNITED STA TES PATENT OFFICE.

EDWARD E. STEVENSON, OF LOS ANGELES, CALIFORNIA, ASSIGNOB, BY MESNE .ASSIGN- MENTS, TO EMSCO DERRICK & EQUIPMENT COMPANY, OF LOS ANGELES, CALI- FORNIA, A CORPORATION OF CALIFORNIA.

PUMP-BOD SUSPENSION DEVICE.

Application filed October 5, 1926. Serial No. 139,620.

This invention has to do generally with devices for suspending pump rods from the walklng beams whereby they are-adapted to be recip-rocated, and has as its principalobject to provide a device of extreme simplicity whereby the variable angularity between beam and rod is compensated to a very large. degreeso the pump or polish rod reciprocated thereby may be maintained substantially vertical or have straight-line motion rather than having appreciable inclination from the vertical during its reciprocation.

The desirability of compensating the variable angularity of the beam, and thus reducing rod-bending to a minimum, is very well understood by those skilled in the art, though it may be here briefly mentioned that bending of the rod is harmful in that it tends to over-stress the rod and stufling box through which it reciprocates, and the binding action occurring between a bent rod and its stufiing box causes rapid and undue wear both of the rod and box. Generally, it may be considered as lowering the general efiiciency of the pump apparatus and as reducing the extent of its useful life materially.

Many different devices have been arranged to accomplish the desired result, most of them depending upon more or less complicated connections between the beam and a stationarily; located point on the derrick structure or between the beam and rod hanger. The complications and resulting unreliability of such mechanisms generally defeat their purpose, for service conditions in oilfields are most severe and many of the operators are unequipped properly to care for and make the necessary adjustments of the devices.

v I have therefore devised a very simple compensating device, the compensation being-gained by the peculiar nature and relative arrangements of the hanger elements, rather than by the interposition of mechanism between a hanger and its associated beam. By virture of its simplicity, the device may be made, applied and cared for at minimum cost, and may be so sturdily constructed, without being over bulky or of excessive weight, that it is well adapted to stand up under severe service conditions.

tions out of the position of Generally, the device may be described as I an articulated hanger or stirrup depending from the beam. The stirrup is so appliedto the beam and to the polish rod that its jointed action during reciprocation of the beam maintains the point of rod or load application substantially in vertical alinement with the stufiing box through which the rod reciprocates, all to the ends enumerated above.

A better understanding of the invention, its advantages, features of novelty and objects will be had from the following specification, reference being had to the accompanying drawings in which:

Fig. 1" illustrates anembodiment of my invention applied to a conventionally illustrated pump operating mechanism;

Fig. 2 is an enlarged fragmentary view of my device in the position it preferably assumes when the walking beam is substan tially horizontal Fig. 3 is a view of Fig. 2 looking from the right thereof Fig. 4 is a fragmentary top plan view of Fig. 2;

. Fig. 5 is a view similar to Fig. 2 but showing the relative position of .parts when the walking beam is rotated in I( pposite .direcv ig. 2;

Fig. 6 is a detached plan view of the beam or crown-casting;

Fig. 7 is a side elevation of Fig. '6;

Fig. 8 is an elevation of the upper eyecasting preferably provided at the ends of the pendant hanger links;

Fig. 9 is aside elevation of Fig. 8;

Fig. 10 is an elevation of one of the eyecastings preferably applied to the lower ends of the hanger links;

Fig. 11 is a side elevation of Fig. 10; Fig. 12 is an elevation of one of the transverse links of the device;.

Fig. 13 is a section on Fig. 12;

line I 1313- of 'Fig. 14 is a top, plan view of the cross- I by the beam and connected at their lower ends by a transverse rod-supporting link to which the rod or load is, in effect, applied through a pivotal joint; the points of pivotal connection between the links and rod being arranged in angular relation. My broader claims are directed to such a combination, that is,-a combination wherein only a single pair of pendant, rod-suspension links and a single transverse rod-supporting link is employeth for it will be readily understood that .such'; elements and arrangement are self-sufiicie'nt to accomplish the desired end. However, as a practical feature, I provide a duplicate stirrup assembly or set of linkage" at each side of the walking beam and connect the two transverse links by a cross-head to which the rod is adapted to be applied, the head having pivotal con nection with the two'transverse links. By reason of this symmetrical arrangement, the

. strains are moretifectively taken and disis made more readily.

tributedand connection with the pump rod It is not to be construed, however, thatmy broader claims are in any sense limited to this duplication and interconnection arranger members.

a string of sucker rods (not shown) toa pump plunger (not shown). I

Numeral 18 generally designates the hanger which is the subject-matter of the present application and which forms a driving connection between beam 10 and rod 16 whereby said beam is adapted to reciprocate rod 16 or at least lift said rod, since descension of the rod is ordinarily accomplished solely through gravitation, the connection between the hanger and polish rod being such that they'are capable of relative longitudinal movement during the downstroke so, in the event descension of the rod is unduly resisted from beneath, the beam and hanger may continue their-downstroke without injuring the hanger or the rod and its associated elements.

I 6). As viewed in plan, this block is forked,

the fork arms 22 being adapted to rest on the forked end of the beam, and slot 23 being disposed over slot 14 so the pump rod and trunnions 25" and 26 from the other I side; trunnions 25 and 25 being in axial alinement, as are also trunnions 26 and 26. Preferably, though not necessarily, block 21 is so fashioned and so located on the beam that when the latter is approximately horizontal (Fig. 2) trunnions 25 and 26 are not only substantially in horizontal, alinement but are also substantially equi-spaced from the extended axis of rod 16.

Since the two linkage sets are identical, only one need be described in detail, parts of linkage 20 which are similar to parts of linkage19 being designated by similar reference numerals but with the exponent a. Preferably, though not necessarily, pendant,

rod suspension links 27 and 28 are of equal length and are in the form of rigid straps having eyecastings 29 and. 30 at their oppositeends. However, the word link as here applied to the pendant members 27, 28 and as used in the claims with reference to these members, is used merely to distinguish tension elements between the beam and the th1rd link hereinafter mentioned and they need not necessarily be rigid. There-- downwardly, and. preferably, though not necessarily, inwardly toward the transverse connecting link 32.

preferably, though not necessarily, triangular (Fig. 12) and is adapted to take pins 33 and 34 whereby links 27 and 28, respectively, are pivotally connected through their eyecastings 30 to said link 32, cotter keys 35 or other suitable means being employed to hold:

The third or rod-supporting link 32 is lit) the pivot pinsand eye-castings from dis- 16. Body portion 37 carries axially alined trunnions 38, 39 adapted to be taken pivotally in links 32 and '32, respectively, annular v shoulders 40 and cotter keys 41 engaging the inner and outer sides, respectively, of the links to hold the elements in assembly.

Body member 37 has a medial, vertically extending rod-receiving way 42 which opens to the side thereof, the axis of said way preferably, though not necessarily, lying in the common vertical axial plane of trunnions 38, 39. Any suitablereleasable closure means may be provided for retaining rod 16 in-way 42, but I have illustrated preferred means in the form of a gate 43 pivoted at 44 at one side of the way and ada ted to be swung through sockets 45 across t e way, as illustrated in full linesin Fig.- 14, a keeper pin 46 being dropped through lugs 47 to hold the gate releasably in closed position. 1

Rod 16 has a downwardly facing, annular shoulder adapted to rest on top body'member 37 when the rod is within the way. This shoulder48 (Fig. 3) is conveniently, though not necessarily, formed by the lower end-of usual rod-clamp 49, said clamp. being ad: justablelongitudinally along t e rod and a being held in adjusted position by clamp made of only one set of linkage,\for it will be apparent the two sets are similar throughscrews 50, The rod and its load are thus applied to links 32, 32 through head 36, and the latter has pivotal connection with said links through trunnions 38, 39. It will be immediately apparent that with gate 43 swung to open position (dotted lines in Fig. 14) the hanger, as a whole, may be swung about the trunnions on-casting 21 towards or away from the polish rod and thus move head 36 into or out of rod engaging position.

In setting forth thefollowing relative positions of pivot points, etc.,"mention need be out and that, with the polish rod pivotally applied to one, only, of the transverse links, one set of linkage, alone, is competent to perform the functions ascribed "to the pair of inter-connected linkage sets.

I also'make the reservation that while I will hereinbelow set forthrelative positions 7 pivot points, etc;, which give particularly good results I these relative positions may .be

varied-within reasonable limits without departing-from the spirit and scope of my in- H'vention,{considered in its broader aspects, andftherefore only such claims as specify particular relationships new be considered as limited to such re ationships;

In pointing out these relationships it will i be helpful to consider the beam in the ap- 23 proximately horizontal position of Fig. 2,

though certain of the relationships change and others are constant when the beam moves out of horizontal.

Pivot points 25 and 26 are in horizontal alinement and are equi-spa'ced fromthe extended axial planeof rod 16,- pendant links 27 and 28 are of substantially equal length and incline inwardly to trunmons 33' and 34, respectively, which trunnions are also in horizontal alinement and equi-spaced from the axis of rod 16. Trunnion or ivot point ,38 is between and below trunnidns 33, 34

and equi spaced therefrom, the angle a (Fig. 12) ineluded'between axial planes common to trunnion 38 and the individual ivot pins preferably,'thou 11 not necessarily, It will be seen that I the rod 15 applied, in effect, to. link 32 at a ein g approximately 90.

point which is axially offset from trunnions 33 and 34.

With the above relationships existing and I with a downbeat-in load" applied ,to the cross-head, or, in eii ect, to link 32, upward movement of beam 10 (see full'lines in Fig.

5) draws heads 36 upwardlyagainst clamp 49 andthus lifts rod 16, trunnion "38 being controlled. by the linkage so it travels through a substantially vertical path approximately coincident with the extended axis of the rod, there'thusbein practically no tendency toward bendingro a 16.

As beam 10 descends (see dotted lines in Fig 5) rod 16 gravitates, normally holding shoulder 48 in Contact with the upper face of cross-head 36. During the descension of the beam, the linkage controls the movement of trunnion 38 so it travels. substantially straight downward. \During the up and down strokes of the beam, it will be evident that link 32 moves pivotally about trunnion 38 andthat the variabledistance between said trunnion and trunnions 25 and 26 (and hence the variable angularity between the beam and rod) is substantially compensated by this pivotal movement.

in wa 42 permittlng (this) the upper end.

of sai rod avoidinginterference with beam 10 and casting 21 by virtue of slots 14 and It will be understood the drawings and descriptions are to be considered merely as illustrative of and not restrictive on the us it will be seenfthat I have provided become sandedbroader claims appended hereto, for'various changes in design, structure and arrangement may be made without departing from the spirit and scope ofsaid claims:

I elaim:

1. In combination with a walking beam and a polish rod, means operatively connecting the beam and rod and including a pair of links pendantly su ported from points spaced longitudinally albng the beam, and a third link, connecting the pendant links near their lower ends, the rod being applied, in effect, to the third link at a point axially offset from the connections between the links.

2. In combination with a walking beam and a polish rod, means operatively connecting the beam and rod and including a pair of links pendantly supported from points spaced longitudinally along the beam, a third link connecting the pendant links near their lower ends, and a pivotal connection between said rod and third link at a point axially offset from the connections between the links.

3. In combination with a walking beam and a polish rod, means operatively connecting the beam and rod and including a pair of links pendantly supported from the beam, a third link connecting the pendant links near their lower ends, and a pivotal connection between said. rod and third link;

said pivotal connection being between and below the oints of connection of the third link with t e. pendant links.

4. In combination with a walking beam and apolish rod, means operatively conmeeting the beam and rod and including a pair of links pendantly supported from the beam, a third link connecting the pendant links near their lower ends, and a pivotal Y connection between said rod and third link;

said pivotal connection being between the points of connection of the third link with the pendant links; there being an angle of approximately 90 included between lines connecting the pivotal connection and said points of connection of the third with the pendant links.

5. In combination with a walking beam and a polish rod, means operativcly connecting the beam and rod and including a pair of links pendantly supported from the beam,

a third link connecting the pendant links near their lower ends, and a pivotal connection between said rod and third link; said pivotal connection being between, below and equidistant from the points of connection of the third link with the pendant links.

6. In combination with a walking beam and a polish rod, means operatively connecting the beam and rod, said means including two sets of linkage; each set including a pair of links pendantly supported from the beam, and a third link connecting the pendant links near their lower ends; and a cross-head connecting the third links of the two sets at points axially offset from the connections between links, said head being adapted to take the rod.

7. In a device for supporting pump rods vfrom walking beams, a pair of links adapted to be supported pendantly from points spaced longitudinally along the beam, a third link connecting said pendant links near their lower ends, and a head applied to the third link at a point axially offset from the connections between links and adapted to take a pum rod.

In witness t at I claim the foregoing I have hereunto subscribed my name this 8th day of Sept. 1926. EDWARDE. STEVENSON. 

